I'm confused. After 28 years of reloading I've come across something that I never experienced before. My case length has shrunk. Case length for the 30-06 is 2.494 and after two rounds with the brass it is measured between 2.480 to 2.486. After shooting the brass twice and full length resizing you would thing that the brass would stretch. Can someone out there tell me what is going on? It will be appreciated.....thank you!
My Brass is Shrinking.
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I'm confused. After 28 years of reloading I've come across something that I never experienced before. My case length has shrunk. Case length for the 30-06 is 2.494 and after two rounds with the brass it is measured between 2.480 to 2.486. After shooting the brass twice and full length resizing you would thing that the brass would stretch. Can someone out there tell me what is going on? It will be appreciated.....thank you!
The brass is Nosler Custom and was fired in a Pre 72 model 70. The dies are RCBS. What is the shortest brass a person can shoot. Can I shoot safely and effectively with brass that measures 2.480 out of a 30-06 instead of 2.494 or 2.484? Thanks!
There is no reason that you can't use brass measuring 2.48".In fact,most factory brass is actually shorter than the standard length listed for the cartridge.That is why I asked if you had actually measured the new brass before using it.The important thing is not to exceed the 2.494" dimension,or you could run into problems.
just having some fun
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is there a chance you are using
A small Base die set ?
using low to med reloading data ?
Using cast lead bullets ?
have you reloaded brass more than 5 times ?
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I do not think it is a problem, just keep checking it after every resizing and trim when it gets too long
A small Base die set ?
using low to med reloading data ?
Using cast lead bullets ?
have you reloaded brass more than 5 times ?
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I do not think it is a problem, just keep checking it after every resizing and trim when it gets too long
I found some info on this phenomenon while looking for some reduced power loads. Apparently, this could be normal with low pressure/power loadings. Here's why:
When the cartridge is fired, the firing pin drives the cartridge foreward in the chamber. When the powder ignites, the primer starts to unseat itself from the pocket due to pressure. The recoil/backpressure pushes the head of the case back against the bolt face, reseating the primer. It is at this point that the case expands to fill the chamber. If you're shooting loads that do not produce enough pressure, the case can "expand" while in the "forced foreward" position, as there is not enough pressure to force the case back against the bolt hard enough/long enough. Because of this, your brass can "shrink".
When the cartridge is fired, the firing pin drives the cartridge foreward in the chamber. When the powder ignites, the primer starts to unseat itself from the pocket due to pressure. The recoil/backpressure pushes the head of the case back against the bolt face, reseating the primer. It is at this point that the case expands to fill the chamber. If you're shooting loads that do not produce enough pressure, the case can "expand" while in the "forced foreward" position, as there is not enough pressure to force the case back against the bolt hard enough/long enough. Because of this, your brass can "shrink".
The most relevant question still has not been answered.He mentions that the brass measured from 2.48" to 2.486" after two firings,but he still hasn't told us if he actually measured the new brass before loading it and firing it.He posted"Case length for the 30-06 is 2.494",but he still hasn't confirmed that the new brass actually measured 2.494".
I just measured up some brand new brass.I don't have a 30-06,so I will post the brass lengths that I do have.
22 Hornet Standard case length 1.403" actual new brass measures 1.395"
223 Standard case length 1.760" Actual new brass measures 1.750".
I just measured up some brand new brass.I don't have a 30-06,so I will post the brass lengths that I do have.
22 Hornet Standard case length 1.403" actual new brass measures 1.395"
223 Standard case length 1.760" Actual new brass measures 1.750".
I can't remember the case length when I purchased it, however; I do remember measuring several and they were consistant in length. My best guess is that it was either 2.494 or 2.484, I think it was the later. Regardless, I measured others that are 2.478 and don't understand why the brass is shrinking. I did not trim the necks,(didn't have to) only champered and bevelled. My load is 61.5 gr. of Reloader 19 using a 150 gr. Nolser Accubond. Go figure.
Well, the old time farmers knew a thing or three. They said if you butchered pigs when the moon was waning, the hogs would shrink in weight.
Therefore, you always butchered hogs while the moon was getting bigger, just before the moon was full, to get full sized pork.
Are you shooting that ammunition while the moon is waning? That might be the cause of the cases shrinking!
Therefore, you always butchered hogs while the moon was getting bigger, just before the moon was full, to get full sized pork.
Are you shooting that ammunition while the moon is waning? That might be the cause of the cases shrinking!
I would measure a new case, a fired case, and one after FL sizing, to try and see where things are changing. A more frequent issue is the opposite. The expander ball drags in the ID and actually stretches the case when pulling through the expander. Do you lube the neck ID? Less/no lube may give you a little more pull back. If you have a method to measure the shoulder to base of the case a before and after sizing measurement would be telling. You may be pushing the shoulder back a bunch. One method to avoid that is to set your sizing die so you only push the shoulder back 0.001", or not at all. Just do a 2/3 sizing of the neck, if the case will chamber well for you after the partial FL sizing.
- Location
- Ft. Mac. Alberta
I would load it , shoot it, and trim it to length , then forgetabout it!
Too often we get worked up over stuff that doesn't amount to a hill of beans - this being one.
Cat
Too often we get worked up over stuff that doesn't amount to a hill of beans - this being one.
Cat
I do lube the inside of the neck with a Q-tip and I think you just hit the primer on the head Ron because I was thinking the same. When I go to the range sometime in February I'm going to use that brass in my newly purchased Krico Model 700. When I full length resize I will not lube the inside of the necks. I'm still open to thoughts on this subject and would like to thank everyone for helping.
- Location
- Haliburton County, Central Ontario
I didn't hear any mention of the two case measurement standards (i.e. 'trim to' length and 'maximum' length). Waxing and waning aside, all brass should be kept within these parameters, regardless of other considerations, without confusing these two numbers. Shorter than maximum length (within reason) - okay. Longer than maximum length - not okay. Just want everyone to be safe here...
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